Summary of Organization and Significant Accounting Policies - Schedule of Carrying Value and Fair Value of Financial Instruments (Detail) - USD ($) $ in Thousands |
Mar. 28, 2015 |
Dec. 27, 2014 |
Dec. 28, 2013 |
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|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Debt Instrument [Line Items] | ||||||||||||
| Long-term debt, Carrying Value | $ 1,062,693 | $ 1,064,917 | $ 662,987 | |||||||||
| Level 2 [Member] | ||||||||||||
| Debt Instrument [Line Items] | ||||||||||||
| Long-term debt, Fair Value | 1,105,240 | [1] | 1,101,873 | [1] | 696,500 | |||||||
| Long-term debt, Carrying Value | 1,062,693 | [1] | 1,064,917 | [1] | $ 663,000 | |||||||
| Level 3 [Member] | ||||||||||||
| Debt Instrument [Line Items] | ||||||||||||
| Current portion of deferred consideration and noncompete obligations, Fair Value | [2] | 21,076 | 16,027 | |||||||||
| Long term portion of deferred consideration and noncompete obligations, Fair Value | [3] | 40,058 | 37,357 | |||||||||
| Current portion of deferred consideration and noncompete obligations, Carrying Value | [2] | 21,076 | 16,027 | |||||||||
| Long term portion of deferred consideration and noncompete obligations, Carrying Value | [3] | $ 40,058 | $ 37,357 | |||||||||
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